 You can't see it, you can't feel it, you forget about it, but it's there. Every time you press the foot pedal in the catheter laboratory you are delivering X-rays to the patient but also to yourself and other people in the room. After years of performing angiography and coronary intervention what is the effect of all that X-ray exposure on the operator?
This is an important issue for cardiologists and radiologists who frequently perform interventional procedures. When we enter the catheter laboratory we dress for battle. Lead skirts and tops are worn, a thyroid shield and sometimes lead glasses. However the number and complexity of interventional cases is rising and with it radiation exposure. The trunk, thyroid and eyes may be protected the head is completely exposed. So this leads the first question: Is there a higher risk of brain tumours in interventional cardiologists? In 2012 data was presented on 9 interventional cardiologists and radiologists with left sided brain tumours. The paper was small and could not prove a link but the authors invited doctors to report any other cases they were aware of. This resulted in a second publication in 2013 reporting data on an extra 22 cases of brain and neck cancers from around the world in 23 interventional cardiologists, 2 electrophysiologists and 6 interventional radiologists. All of them had worked for prolonged periods (23.5±5.9 years) in active interventional practice with exposure to ionizing radiation in the catheterization laboratory. In 26 cases data was available regarding the side of the brain involved and 85% were on the left. In response to this Worldwide Innovations and Technologies now produce a lightweight (50g) disposable surgical cap called the "No Brainer" which reduces radiation exposure to the head of the operator by more than 80%. If your catheter laboratory doesn't have them perhaps you should be asking why? What about other parts of the body? Chronic radiation exposure to the skin of the legs occurs and there are reports of some interventional cardiologists noticing the onset of leg hair loss caused by chronic occupational radio-dermatitis. The introduction of shin protection markedly reduces radiation exposure to this area. We have personal dosimeters in the catheter labs but they are worn inconsistently and no feedback is given on the exposure recorded from them. Even if we did get the data it is retrospective and does not allow for any rapid changes in practice. Reducing screening and acquisition time is important but this comes with experience. I try and instil into my fellows the importance of performing the procedure with the shortest possible screening time and for an uncomplicated radial approach coronary angiogram it possible to shorten this to less than 1-2 minutes. Using the fluoro-acquire function during angioplasty also greatly reduces the number of formal acquisitions and therefore the radiation dose. What if you were to give operators immediate feedback on radiation exposure. This has recently been examined in the RadiCure study. This showed that wearing a personal real time radiation-monitoring device that beeps faster as radiation exposure increases reduces radiation exposure by a third. The study used the interactive Bleeper SV device and the immediate feedback allows cardiologists to make changes during a procedure to reduce X-ray exposure such as adjusting the radiation protection shield, moving further away from the X-ray source or reducing the frame rate. Radiation protection not regarded as the most exciting subject when taught as part of an IRMER course at the beginning of you career as an cardiology trainee. I believe that introduction of better protection to the head and legs and the use of real time radiation protection devices would be of valve in improving catheter lab safety for the operator. I would value any comments from people who have used the Bleeper SV device or the No Brainer head protectors.
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 The famous painting 'Girl with a Pearl Earring' (Meisje met de parel) by Johannes Vermeer has been in the Mauritshuis in The Hague since 1902. The painting has stimulated much interest and was the inspiration of a bestselling novel by Tracy Chevalier. Painted around 1665 it shows a girl under a blue and yellow headscarf with a mysterious and enchanting gaze. On her ear hangs a glittering jewel, a pearl. But despite the name of the painting is the girl really wearing a pearl? Recently Vincent Icke, professor of theoretical astronomy at Leiden University, has challenged this idea. His hypothesis, that the pearl is not a pearl at all, is based on the observation of reflections from the painting. Since pearls consist of thin layers of calcite they should scatter light of different wavelengths to create a soft white pearly lustre. In contrast the jewel in the painting has a bright reflection in the left corner and causes a reflection in the girl's collar. The dark part of the earring resembles the girl's skin and rather than pearl perhaps it is a silver or polished pewter earring.
What has this got to do with cardiology? Sometimes it is necessary to challenge the accepted view and take a closer look to reflect on where truth lies. Take the use of adrenaline in cardiac arrest. Ask anyone and they will tell you that during cardiac arrest you need to give adrenaline. If you have ever given adrenaline in this situation you will testify to its effects on blood pressure. For this reason adrenaline is regarded as essential for successful return of circulation after cardiac arrest. However recently people have started to challenge this idea and ask whether adrenaline is really that useful. A recent study looked at the relationship between pre-hospital use of adrenaline and survival in people with out-of-hospital cardiac arrest. There were 1,556 patients of which 73% received adrenaline and 17% of these had a good outcome versus 63% of those who did not receive adrenaline. The adverse effects of adrenaline were observed regardless of length of resuscitation or in-hospital interventions performed. The adjusted odds ratio of intact survival was 0.48 for 1 mg of adrenaline, 0.30 for 2 to 5 mg and 0.23 for >5 mg. Therefore in a large group of patients who achieved return of circulation, pre-hospital use of adrenaline was consistently associated with a lower chance of survival. Taken together with other observational studies there is now a randomised controlled trial called PARAMEDIC2 which will administer adrenaline or placebo to cardiac arrest patients and should help to address the question of whether it is help or harm in cardiac arrest. It is worth remembering that before the 1950's adrenaline and other pressor agents were used as standard treatment for all types of shock and it wasn't until later that there came an understanding that this was harmful and that fluid resuscitation was in fact required in most cases. In September this year a 51 year old man committed suicide at home. Normally this wouldn't have been reported in the press and even though the man in question was Stefan Grimm, a Professor of Toxicology from Imperial College London this was hardly the subject of national news. When people commit suicide sometimes they leave a note which might be read by their family, the police and the coroner. This professor, however, decided to send a note by email to the staff in his institution and as we have now found out the contents were deadly. The email has been widely circulated and has made national headlines and uncomfortable reading for Imperial College. According to the message his suicide was triggered by the pressure he found himself under from the College to obtain external grant funding. He felt worthless and in a state of despair.
What started as a small story in the Times Higher Education Supplement went viral when the email was published by David Colquhoun, Emeritus Professor of Pharmacology at UCL on his widely read DC Science blog. Servers crashed and the story spread through social medial finally ending up in the Daily Mail which in true tabloid journalist style informed us that it was a row about cash, that the professor had gassed himself and featured comments from his elderly next door neighbours about what a nice, but quiet man he was. The Grimm email pulled no punches and named names in the Faculty of Medicine. Reading It and seeing the reaction of academics on social media it clearly touched chords with many of them who have anxiety about their ability to publish and gain large amounts of external grant funding. Whether or not the original email was authored by Stefan Grimm himself is not proven but at present no-one seems to doubt that it was. Its contents detailing the mechanisms by which top universities deal with failure to perform is familiar to many researchers. It used to be that scientists were judged on output in the form of papers but now universities have to keep an eye to the financial bottom line. So professors, at least from Imperial College, must also raise the equivalent of £200,000 per annum of grant income to remain on the faculty. This effectively means they need to be awarded a large programme grant of £1 million over 5 years and email's from Stefan's head of department make this crystal clear and what the consequences of failure would be. Much has been written about Stefan Grimm although most admit they did not know him. I worked in the Department of Experimental Medicine at Imperial College where he was based for 2 years between 2005 and 7. My desk was just a few feet from his office and I saw him most days. I can't say I really knew him well, I don't know who did, but I have no doubt about his strong commitment to science and his ability to work hard. He usually arrived before nine in the morning and didn't leave until after nine at night. His research was complex (in other words difficult to understand) but his students and post-docs respected him and he was very supportive. Stefan was not socially extravert and what seems clear now from the reports is that the informal performance management process resulted in frustration, despair and almost certainly depression. Looking at this from outside he might be regarded as a person very much at risk of suicide in those months leading up to the tragic event. A single man, somewhat introverted, wedded to his work and perhaps without a large social network of friends to turn to for support. The lesson for those senior faculty members at Imperial College who handle performance management is to be minded to the possibility of that depression may be triggered or if already present worsened in staff subject to these processes. When an academic fails to be awarded grants or their research output falters it is not usually through laziness or disinterest. Most scientists I know live and breathe their work spending hours in the evenings and weekends working on papers and grants. A reasonable question to ask when research output falls is whether the scientists could be suffering from depression and consider the consequences of further stress. Any engineer will tell you that the way to protect a structure under stress is not to increase the load it has to carry. if you do it is likely to snap and in people that has severe and irreversible consequences. We are told that Imperial College is now conducting a review. That won't change what has happened to Stefan Grimm or atone for any injustice that may, or may not, have been served on him. But lessons need to be learned and perhaps the greatest one is to be mindful of the possibility of depression and to support staff placed under informal or formal performance management in order to minimise the risk of a tragic outcome. |
Dr Richard BogleThe opinions expressed in this blog are strictly those of the author and should not be construed as the opinion or policy of my employers nor recommendations for your care or anyone else's. Always seek professional guidance instead. Archives
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